All about oyster shell?

My hens shells are weak and occasionally misshappen. I have offered them oyster shell, but this has not helped
Do any of you mix them in with their feed? Can you overfeed oyster shells? Could they need something else? They are fed layer pellets.
I have looked up diseases that cause weak eggs, but my hens have no other symptoms. I have heard of egg drop disease, but so far that only exists in foreign countries. My hens are only a yeAr old.
Does anyone know what else I could try?
Thanks!!

By misshaped do you mean long, pointed, round? That is usually genetic.

Do the shells have "wrinkles in them? That is usually a disease.

Are the shells "banded"? Usually age, generally not flock wide.

Thin shells flock wide- lack of Vitamin D to help assimilate the calcium. Common in older hens, very high producers, old or poorly formulated feeds, something inhibiting Vitamin D, there are times that very hot hens pant to much and have a problems with CO2 which messes up both calcium and Vitamin D. The double whammie.

Mine don't eat oyster shell either. If you are feeding layer feed, that *should* be enough but if the shells are still a little thin, I'd forget oyster shell and try crushing up some egg shells and use those instead. Mine love the crushed egg shell and despite the popular belief that it will cause them to become egg eaters, I really don't think they make the connection between those itty bitty bits of yummy shell in the bowl next to the feeder, and the big round things that occasionally land in the nest box.

I had a few weak egg shells and so I started buying oyster shells... I had them in a little tray and they seemed to ignore them so I started scattering it with their scratch and it helped.
I have also heard that giving them eggshells helps, but I would REALLY make sure there is no egg remnants on the shell, just because I have had issues with egg-eating chickens which I think stemmed from them eating an egg that accidentally broke in the nesting box.... Just rinse the shells with warm water and crush them and see if that helps.

So specifically answering a few of your questions:
YES I have found mixing shells with scratch has encouraged them to eat it
and NO I dont believe you can overfeed them with oyster shells, they are able to discern how much they want for themselves. If youre giving too much oyster shell I've found that mine just dont eat it.

Hi, sometimes the eggs have wrinkles. Sometimes one is pointy. Tthe eggs are weak with a rough chalky shell. It is hot here, but I had this problem when it wasn't hot too. What diseases cause wrinkled eggs??
Thanks a million everyone

Quote:Typically wrinkled eggs are from hens that have recovered from Infectious Bronchitis, even if they got the disease as pullets. Diseases confined to the uterus on individual hens may also cause this as a permanate condition. An egg being pointed is usually genetic or a congenital situation.